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arXiv 2302.04902cond-mat.mtrl-scicond-mat.mes-hall
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周期势中的激子

Excitons in periodic potentials

Dinh Van Tuan, Hanan Dery

AI总结:

本文将激子建模为与 Wigner 或 Moiré 电子晶格周期势耦合的点状偶极子,利用群论分析可光耦合能带及其随势周期的能量移动,以解释电子密度和晶体有序性对亮激子蓝移及单层半导体吸收的影响。

摘要:

本文研究了激子在周期势中的能带结构,这些周期势由激子与 Wigner 晶格或 Moiré 晶格中电子之间的短程相互作用产生。将激子视为与周期势相互作用的点状偶极子,我们可以求解一个简单的单体问题,从而在多体问题情境中提供有关激子的有价值信息。通过运用群论,我们识别出能够与光耦合的激子能带,并随后量化其在势周期发生变化时的能量移动。该方法使我们能够模拟光学活性激子和 trion 态对电子密度变化的响应。我们获得了关于 Wigner 晶体中电子有序性与亮激子能量蓝移之间关系的重要认识。我们还在单层半导体的光吸收实验背景下讨论了这一关系的后果。

英文摘要:

The energy band structure of excitons is studied in periodic potentials produced by the short-range interaction between the exciton and electrons of Wigner or Moiré lattices. Treating the exciton as a point-like dipole that interacts with the periodic potential, we can solve a simple one-body problem that provides valuable information on excitons in many-body problem settings. By employing group theory, we identify the excitonic energy bands that can couple to light and then quantify their energy shifts in response to a change in the period of the potential. This approach allows us to emulate the response of optically active exciton and trion states to a change in electron density. We gain important insights on the relation between the electron order in a Wigner crystal and the energy blueshift of the bright exciton. We discuss the consequences of this relation in the context of optical absorption experiments in monolayer semiconductors.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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